(a) Technical Field
The present disclosure relates to an aluminum alloy. More particularly, the present disclosure relates to an aluminum allow produced by a continuous casting technique that bestows improved elasticity characteristics to the resulting aluminum alloy, and a method for producing the same.
(b) Background Art
Aluminum alloys improve the properties of aluminum and displays many excellent properties, which can be varied according to the composition of the alloy. For example, high strength aluminum alloys, such as duralumin, can be made by including copper, which provides high strength characteristics to the alloy. Increasing the copper content in the alloy has the effect of increasing the strength of the alloy. For example, super duralumin is created by adding copper to the duralumin, and extra super duralumin is created by adding copper to super duralumin. Extra super duralumin is used as an aircraft material. Disadvantageously, such high strength aluminum-copper (Al—Cu alloys such as duralumin lack the ability to resist corrosion (i.e. they are prone to corrosion). Structural aluminum alloys are typically made by adding magnesium and zinc, which confer excellent corrosion resistance properties to the alloys. Accordingly, such structural aluminum alloys are used for railway vehicles, bridges, and the like. Aluminum alloy for casting can be made by adding Si, and other metals can be mixed with Al to create alloys with a variety of other properties, such as heat-resistance and brilliance.
Aluminum alloys are largely divided into two groups: alloys for wrought material and alloys for casting material. The former group includes Al—Cu—Mg-based alloys (e.g., duralumin, super duralumin), Al—Mn-based alloys, Al—Mg—Si-based alloys, Al—Mg-based alloys, and Al—Zn—Mg-based alloys (extra super duralumin) alloys. The latter group includes Al—Cu-based alloys, Al—Si-based alloys (silumin), Al—Cu—Si-based alloys (lautal), Al—Mg-based alloys (hydronalium), Al—Cu—Mg—Si-based alloys (Y alloy), and Al—Si—Cu—Mg—Ni-based alloys (Lo⋅Ex alloy).
Recently, attempts have been made to generate a metal-based compound reinforced with carbon nanotubes (CNT) molded in a powder form, however, use of such a compound is limited because of its high cost. Disadvantageously, when it was applied to a casting process in a powder form, major problems were encountered with dispersion of the powder in an Al matrix. A further disadvantage results from a hypereutectic aluminum casing material that can only be made by a low pressure casting process. A further disadvantage is that processing such a material with coarse Si particles poses additional manufacturing difficulties. For example, when Si is used to increase the elasticity of a metal-based compound, or a reinforced CNT material molded in a powder form, the coarse Si particles limited the ability to improve elasticity, due in part to problems with the wetability when combined with the Al matrix, which resulted in uneven dispersion of the CNT powder when used for a continuous casting process. Additionally, the ability to work with such materials is cost prohibitive.
Accordingly, there is a need in the art for an aluminum alloy with high elasticity for use as a casting aluminum material to with improved the rigidity and noise, vibration, and harshness (NVH) characteristics.